From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MSGID_FROM_MTA_HEADER,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD8DAC4346E for ; Tue, 29 Sep 2020 09:29:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 483F520848 for ; Tue, 29 Sep 2020 09:29:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=nxp.com header.i=@nxp.com header.b="IcV41K9t" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728094AbgI2J3A (ORCPT ); Tue, 29 Sep 2020 05:29:00 -0400 Received: from mail-db8eur05on2051.outbound.protection.outlook.com ([40.107.20.51]:31489 "EHLO EUR05-DB8-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727746AbgI2J24 (ORCPT ); Tue, 29 Sep 2020 05:28:56 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=n825kgmhjwzJ6v2NAvc1onL6eJJN9uGVgK5ZgHK7wUZEy0bMkf5CKOOkHT3PNSdNFWRLwkIXRoeBimbXn0oMScA5+xIY4vcp6gQykL8KQhQfc3C+nxgxJcQhjAIgGSDJApl3gTwQ4KWXPJdKRekS7CTi2zteBhMza3DopF/PFDXqNJp2fT75ZePnCJWC7cKVBeY+9pmUGwXPN3xv2DIOVBC6an5tCevFfYhmjAt1HvtFi6vtd5MnSU9R80mpz06delte4+yDMbE2hKOC5vyQOudemrmnFYtq5+pSt6O/D0UL5eNRLZ/80V4dSDb/9FUxeecip5kvvFtWcbvZ48tsjg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=kxFf4h6Bda0HiiRWL1zBy3Dnd2jLW4kvNZHM4wsewds=; b=Zvyh4aEHTErSko38KGfKyTN2PAaYxuJf0lpuAbc9kFpJ5FNwhuYAwB/n8GeBY/E8ohiGIsu+WoousghbOuKtCHNvhbmt30vmWWZATx6oZfPgNF/0EfqRf+bUr9lUWpINANeasVlDYnOmD6VRsOGGC8hSc4zvjv8BAJKMEXIxiwacjgUp2N4/NtxeAZqKJ0FGlASwiRT6B7ecke+pkJ8fnpC2Gtmdb/JwAsXh4iWnroj4WgXz5odHJokl5pgKOzGv2iVUCu6a2wco6ZSgvFkk6WHKxsmrcJ7QgApZn+7KFwxslJvq5RXMbz4j0d4NKtAFAoPUBlDR+QD9zBxAdn52fA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nxp.com; dmarc=pass action=none header.from=nxp.com; dkim=pass header.d=nxp.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nxp.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=kxFf4h6Bda0HiiRWL1zBy3Dnd2jLW4kvNZHM4wsewds=; b=IcV41K9tTkp+ZGL+6hTa2qsBj6urLE0CeGAr/MsD9wrpox4FDXfFXAMFubhR/wseJ+6uLNFV4deFcGmCBQn8qMZWIaGg3/AXVF2c2XuU0IBDCjPHFNzc/CqAjC9wwI5F69h1SPDauQpehodxhxTA1Vjf9bbRX9d/CrEvs5Qcrq0= Authentication-Results: linuxfoundation.org; dkim=none (message not signed) header.d=none;linuxfoundation.org; dmarc=none action=none header.from=nxp.com; Received: from DB6PR0402MB2760.eurprd04.prod.outlook.com (2603:10a6:4:a1::14) by DB6PR0402MB2935.eurprd04.prod.outlook.com (2603:10a6:4:9d::23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3412.25; Tue, 29 Sep 2020 09:28:53 +0000 Received: from DB6PR0402MB2760.eurprd04.prod.outlook.com ([fe80::35c5:8c71:91f3:6bc6]) by DB6PR0402MB2760.eurprd04.prod.outlook.com ([fe80::35c5:8c71:91f3:6bc6%12]) with mapi id 15.20.3412.029; Tue, 29 Sep 2020 09:28:53 +0000 From: Peng Fan To: gregkh@linuxfoundation.org, jirislaby@kernel.org, andrew.smirnov@gmail.com Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, linux-imx@nxp.com, Peng Fan , Fugang Duan Subject: [PATCH] tty: serial: fsl_lpuart: fix lpuart32_poll_get_char Date: Tue, 29 Sep 2020 17:55:09 +0800 Message-Id: <20200929095509.21680-1-peng.fan@nxp.com> X-Mailer: git-send-email 2.28.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: SG2PR04CA0165.apcprd04.prod.outlook.com (2603:1096:4::27) To DB6PR0402MB2760.eurprd04.prod.outlook.com (2603:10a6:4:a1::14) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from linux-1xn6.ap.freescale.net (119.31.174.71) by SG2PR04CA0165.apcprd04.prod.outlook.com (2603:1096:4::27) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3412.21 via Frontend Transport; Tue, 29 Sep 2020 09:28:50 +0000 X-Mailer: git-send-email 2.28.0 X-Originating-IP: [119.31.174.71] X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-HT: Tenant X-MS-Office365-Filtering-Correlation-Id: d38cb754-bc4c-457b-36d0-08d8645a146c X-MS-TrafficTypeDiagnostic: DB6PR0402MB2935: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:3968; X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 4VrN+R6HWq20/H9oLldUlV/Ccj7GZyvH/sivFCS/OrxOgH09mynSttD0gEiETLgcuOYSqVJd4ZGkss5ft4+yBp6hHdTGbeH6kIo3kVyUJcvUWZvgu4p9nl1pZ1Z8jnwPW+FX6VWNQMZWiWe2OPIItVrskNuQnxRTmIZdofEUm36pQGLbmEh/qQs8jFhajVZb1q+tx7JLqEeieBD1A0nzCC/YSzSMeqeDRnSZI1tYtsmAj5RbX0+dMJt9MGIYU70x6LXXtOdEtBVWPbqho1vYW70WUBqJbrBWYL6hgSfbNv3YlOQOfE43xwG29BOu7+17OrvJcSyvi/3Kyx6qkO4tZMFyltO1iKVYwq6WvkhDFNsQYPn/pKXHD2lMTivYKDCJ X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DB6PR0402MB2760.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(366004)(346002)(376002)(39860400002)(136003)(396003)(6486002)(16526019)(54906003)(6666004)(5660300002)(66556008)(316002)(66476007)(4744005)(8936002)(6506007)(2906002)(186003)(478600001)(86362001)(26005)(44832011)(36756003)(6512007)(52116002)(956004)(2616005)(8676002)(66946007)(1076003)(4326008)(83380400001);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData: 6bDkTo+9uGRRHrwTbX+lvCltdhlrj4OWcwosoo4W5DGV0k/BICAqI+IQtBeK95OBcCWYrNZkKZ6zp3V5rKsIee0qvnqn0+otSJp+pDvM1iAmjeBImh2lcSYXVsR6irN6gCIb6DtILfuAvMHw8tDP+a+JKOMKMeRvDTUd2MNk6X+bPiCihMwt+cytRLLmlY619GalTpsPguhaMN2Qbg25xyQeffNHz0zoO65ptrsgxHVWsiHiQiqrkqboinjs24tsJVdcSW+gJ87uIT7UnsfJ84vF6hShRpkxXcRNedFmcdWXEgKWfCLSDMTQjLsQIgwXv/Q3/oQUYtiYET/ryskYsFORW1ESHyAXT5ycYvkWmwwXACl92eJYK4v48RX0EaJ+4ToB0gfNk5cbD+g1XUhAS3ykjbZG8FN9xNWvgLftj0Cc/UyJnGSxjsWXzdqRb4DMdxk57CI8on0DGu93T9gYecqDMC1oZMZ5hP/4fjz9mFwbldNFpxXkf0GPW/DjHT56wR9ACoIODYEE9R1pFy/oSH1ZT8+oQX7J3WzgHZhHuzGrrzU4g/kQIexkEDzE55/ae0Prhab3FvS4pmlUG4Nf0UwmDwyVqb/fGDnaWkxFFTe+GGqt+GKK2vgZazIyMbNK8pbNIL8fYO4vKsnjrVXGOw== X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: d38cb754-bc4c-457b-36d0-08d8645a146c X-MS-Exchange-CrossTenant-AuthSource: DB6PR0402MB2760.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Sep 2020 09:28:52.9133 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 3DptnmsAlgISLzSsmqhQHPipoiKyVIHvayymF1u/5RrMqhUQsy7jFBqLXuxSmoBWNBmlD34sKmv7GOSOhFwrew== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB6PR0402MB2935 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The watermark is set to 1, so we need to input two chars to trigger RDRF using the original logic. With the new logic, we could always get the char when there is data in FIFO. Suggested-by: Fugang Duan Signed-off-by: Peng Fan --- drivers/tty/serial/fsl_lpuart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 645bbb24b433..1c37280b6c0c 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -680,7 +680,7 @@ static void lpuart32_poll_put_char(struct uart_port *port, unsigned char c) static int lpuart32_poll_get_char(struct uart_port *port) { - if (!(lpuart32_read(port, UARTSTAT) & UARTSTAT_RDRF)) + if (!(lpuart32_read(port, UARTWATER) >> UARTWATER_RXCNT_OFF)) return NO_POLL_CHAR; return lpuart32_read(port, UARTDATA); -- 2.28.0